Function: adjoin
adjoin is a function alias for cl-adjoin, defined in cl-lib.el.gz.
This function is obsolete since 27.1; use cl-adjoin instead.
Signature
(adjoin ITEM LIST [KEYWORD VALUE]...)
Documentation
Return ITEM consed onto the front of LIST only if it's not already there.
Otherwise, return LIST unmodified.
Keywords supported: :test :test-not :key
Aliases
adjoin (obsolete since 27.1)